CRUSTACEOLOGY. 



411 



Arachni- 

 des. 



Family IX. Araneides. 



Mandibles terminated by a simple hook or nail ; ab- 

 domen connected closely with the thorax ; anus with 

 nipples. 



I. Feet not formed for leaping. 



1. Hinder eyes not placed on the anterior and supe- 

 rior part of the thorax ; not forming an irregular hex- 

 agon. 



A. The two exterior nipples longer than the rest, 

 cylindrical, and projecting. Lip not advanced between 

 the maxillae, nor prominent, but much longer than 

 broad. 



a. Mandibules projecting. 



Genus XXVI. Mygale. Palpi inserted on the ex- 

 tremities of the maxillae. 



Genus XXVII. Atypus. Palpi inserted towards 

 the base of the maxillae. Lip quadrate, not prominent. 



Genus XXVIII. Eriodon. Palpi inserted towards 

 the base of the maxilla- ; lip prominent, long, and nar- 

 row. 



b. Mandibules perpendicular. 



* Six eyes. 



Genus XXIX. Segestria. Eyes disposed in a 

 transverse line, crooked behind, at each extremity. 



Genus XXX. Dysdera. Eyes disposed in nearly 

 an oval form, open in front. 

 ** Eight eyes. 



Genus XXXI. Filistata. Maxillae much inclined 

 towards the lip ; with no sinus or groove at the inser- 

 tion of the palpi, they being inserted at the hinder side. 

 Lip much longer than broad. The fourth, then the 

 first pair of feet, longest. Eyes placed on an uneven 

 elevation ; the four anterior ones forming a semicircle 

 open in front ; the four hinder ones disposed in a near- 

 ly straight and transverse line. 



Genus XXXII. Drassus. Maxillae much inclined 

 towards the lip, with no groove at the insertion of the 

 palpi. Lip longer than broad. The fourth pair of 

 feet, and then the first, longest. Eyes not placed on 

 an elevation, disposed in two slightly curved (nearly 

 straight) lines ; those of the hinder line not geminated. 



Genus XXXIII. Clotho. Maxillae much inclined 

 towards the lip, without a groove at the insertion of 

 the palpi. Lip not much longer than broad. The 

 fourth pair of feet, then the second, afterwards the 

 third, longest. Eyes close, disposed in four and four, in 

 two transverse lines, bent slightly backwards in an 

 arched and somewhat concentric manner ; those of the 

 hinder line disposed in pairs, (geminated.) 



Genus XXXlV. Clubiona. Maxillae nearly straight, 

 with a groove at the insertion of the palpi, the apex 

 rounded, and obliquely truncated on the inside ; evi- 

 dently longer than the lip. Eyes disposed four and 

 four in two trans verse lines ; the anterior line straight, 

 the posterior much longer, bent slightly backwards. 



Genus XXXV. Aranea. Maxillae nearly straight, 

 with a groove at the insertion of the palpi. Apex round- 

 ed, the internal angle truncated, remarkably longer than 

 the lip. Lip nearly equal. Eyes disposed in two lines, 

 bent backwards. 



Genus XXXVI. Argyroneta. Maxillae nearly 

 straight, with a groove at the insertion of the palpi. 

 Lip shorter than the maxillae. The four middle eyes 

 disposed in a quadrate form, the lateral ones geminated. 



B. All the nipples short, and nearly equal, of a conic 

 form. Lip projecting between the maxillae, being much 

 •broader than long. 



a. Eyes not describing the segment of a circle. 



* Maxillae straightened towards their extremities, not Arachni 

 dilated. des - 



Genus XXXVII. Scytodes. The first and the *" 

 fourth pair of feet longest. Eyes six. 



Genus XXXVIII. TuERinioN. The first and the 

 fourth pair of feet longest. Eyes eight ; the four mid- 

 dle ones arranged in a quadrangle, the inferior ones 

 being placed in a common elevation ; the other two ge- 

 minated, and placed on an eminence on each side. 



Genus XXXIX. Latrodectus. The first, and then 

 the second pair of feet longest. Eyes eight, disposed 

 four and four in two transverse and parallel straight 

 lines. 



Genus XL. Pholcus. The first, and then the se- 

 cond pair of feet longest. Eyes eight ; placed on a tu- 

 bercle ; three on each side in a triangle, and two hi the 

 middle ; anteriorly. 



* Maxilla; dilated at their points, and straight. 

 Genus XLI. Uloborus. The first, and then the 



fourth pair of feet longest. Eyes eight, equal, very mi- 

 nute, placed at nearly equal distances from one another, 

 on two transverse lines. The two middle ones a little 

 nearer than the others ; the anterior line bent back- 

 wards, the posterior bent forwards. 



Genus XLII. Tetragnatha. The first, and then 

 the second pah- of feet longest. Eyes eight, and equal/ 

 disposed four and four in two straight transverse pa- 

 rallel lines. 



Genus XLIII. Linyphia. The first, and then the 

 second pair of feet longest. Eyes eight, the four mid- 

 dle ones forming a square, which is narrow in front, 

 the other four geminated, and placed two on each 

 side. 



Genus XLIV. Epeira. The anterior, and then the 

 second pair of feet longest. The four middle eyes 

 forming an equal-sided square ; the other four placed 

 in pairs, two on each side. 



b The eyes describing the segment of a circle. 



Genus XLV. Episenus. Maxillae straight ; lip 

 much broader than long ; the first, and then the fourth 

 pair of feet longest. 



Genus XLVI. Micrommata. Maxillae straight ; lip 

 much broader than long ; the second feet, and then the 

 first pah longest. 



Genus XLVII. Thomisus. Maxillae inclined; lip 

 much longer than broad ; the second and the first pair 

 of feet longer than the rest. 



2. Hinder eyes placed on the anterior and superior 

 part of the thorax, forming an irregular hexagon. 



A. The anterior feet longest, next to these the second. 

 Genus XLVIII. Oxyopes. Maxillae straight, and 



remarkably longer than the lip ; eyes in four transverse 

 lines. 



Genus XLIX. Storena. Maxillae inclined, muck 

 longer than the lip ; eyes in three transverse lines. 



Genus L. Ctenus. Maxillae straight, and. remarka- 

 bly longer than the lip ; eyes disposed in three trans- 

 verse lines. 



B. The fourth pair of feet longest. 

 Genus LI. Lycosa. Lip much longer than broad ; 



the fourth feet and then the first longest. 



Genus LII. Dolomedes. Lip not much longer than 

 broad ; the fourth pair, and then the second pair, of 

 feet longest. 



II. Feet formed for leaping. 



Genus LIII. Eresus. The four middle eyes form- 

 ing a quadrangle ; on the outside of which the others 

 are placed, as if farming another quadrangle to inclose 

 them. 



